text: /*
   * Copyright (C) 2010 Google Inc. All rights reserved.
   * Copyright (C) 2012 Intel Inc. All rights reserved.
   * Copyright (C) 2016 Apple Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are
   * met:
   *
   *     * Redistributions of source code must retain the above copyright
   * notice, this list of conditions and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above
   * copyright notice, this list of conditions and the following disclaimer
   * in the documentation and/or other materials provided with the
   * distribution.
   *     * Neither the name of Google Inc. nor the names of its
   * contributors may be used to endorse or promote products derived from
   * this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #pragma once
  
  #include "ContextDestructionObserver.h"
  #include "DOMHighResTimeStamp.h"
  #include "EventTarget.h"
  #include "ExceptionOr.h"
  #include "GenericTaskQueue.h"
  #include "ReducedResolutionSeconds.h"
  #include <wtf/ListHashSet.h>
  
  namespace WebCore {
  
  class LoadTiming;
  class PerformanceEntry;
  class PerformanceNavigation;
  class PerformanceObserver;
  class PerformancePaintTiming;
  class PerformanceTiming;
  class ResourceResponse;
  class ResourceTiming;
  class ScriptExecutionContext;
  class UserTiming;
  
  class Performance final : public RefCounted<Performance>, public ContextDestructionObserver, public EventTargetWithInlineData {
      WTF_MAKE_ISO_ALLOCATED(Performance);
  public:
      static Ref<Performance> create(ScriptExecutionContext* context, MonotonicTime timeOrigin) { return adoptRef(*new Performance(context, timeOrigin)); }
      ~Performance();
  
      DOMHighResTimeStamp now() const;
      ReducedResolutionSeconds nowInReducedResolutionSeconds() const;
  
      PerformanceNavigation* navigation();
      PerformanceTiming* timing();
  
      Vector<RefPtr<PerformanceEntry>> getEntries() const;
      Vector<RefPtr<PerformanceEntry>> getEntriesByType(const String& entryType) const;
      Vector<RefPtr<PerformanceEntry>> getEntriesByName(const String& name, const String& entryType) const;
      bool appendBufferedEntriesByType(const String& entryType, Vector<RefPtr<PerformanceEntry>>&) const;
  
      void clearResourceTimings();
      void setResourceTimingBufferSize(unsigned);
  
      ExceptionOr<void> mark(const String& markName);
      void clearMarks(const String& markName);
  
      ExceptionOr<void> measure(const String& measureName, const String& startMark, const String& endMark);
      void clearMeasures(const String& measureName);
  
      void addResourceTiming(ResourceTiming&&);
  
      void reportFirstContentfulPaint();
  
      void removeAllObservers();
      void registerPerformanceObserver(PerformanceObserver&);
      void unregisterPerformanceObserver(PerformanceObserver&);
  
      static Seconds reduceTimeResolution(Seconds);
  
      DOMHighResTimeStamp relativeTimeFromTimeOriginInReducedResolution(MonotonicTime) const;
  
      ScriptExecutionContext* scriptExecutionContext() const final { return ContextDestructionObserver::scriptExecutionContext(); }
  
      using RefCounted::ref;
      using RefCounted::deref;
  
  private:
      Performance(ScriptExecutionContext*, MonotonicTime timeOrigin);
  
      void contextDestroyed() override;
  
      EventTargetInterface eventTargetInterface() const final { return PerformanceEventTargetInterfaceType; }
  
      void refEventTarget() final { ref(); }
      void derefEventTarget() final { deref(); }
  
      bool isResourceTimingBufferFull() const;
      void resourceTimingBufferFullTimerFired();
  
      void queueEntry(PerformanceEntry&);
  
      mutable RefPtr<PerformanceNavigation> m_navigation;
      mutable RefPtr<PerformanceTiming> m_timing;
  
      // https://w3c.github.io/resource-timing/#extensions-performance-interface recommends size of 150.
      Vector<RefPtr<PerformanceEntry>> m_resourceTimingBuffer;
      unsigned m_resourceTimingBufferSize { 150 };
  
      Timer m_resourceTimingBufferFullTimer;
      Vector<RefPtr<PerformanceEntry>> m_backupResourceTimingBuffer;
  
      // https://w3c.github.io/resource-timing/#dfn-resource-timing-buffer-full-flag
      bool m_resourceTimingBufferFullFlag { false };
      bool m_waitingForBackupBufferToBeProcessed { false };
  
      MonotonicTime m_timeOrigin;
  
      RefPtr<PerformancePaintTiming> m_firstContentfulPaint;
      std::unique_ptr<UserTiming> m_userTiming;
  
      GenericTaskQueue<ScriptExecutionContext> m_performanceTimelineTaskQueue;
      ListHashSet<RefPtr<PerformanceObserver>> m_observers;
  };
  
  }
  